Bite The Bullet

Tokyo Marui 50rds Magazine for Hi-CAPA: Is it any good? (2009-09-22)

Note: Using propane instead of 134a gas will increase
the wear and stress in your internal mechanisms and is not recommended.
The purpose of this test is to show you the gas consumption and the consistency
of the shots using a higher output gas therefore any inconsistencies will be
made clearer.

The initial differences you will see on this magazine is
that it's substantially bigger (stating the obvious here) and holding almost
twice as much ammo as the regular 5.1 magazine does, this also provides a much
bigger gas reservoir to hold your propellant in. The markings are also
different from the regular 5.1 magazines as shown in the pictures below along
with the 50 round magazine showing a more shiny black finish as compared to the
5.1 magazine having a less glossy dark grey color.

As you can see from the pictures, the magazine dimensions are slightly
different from the magazine lip being taller on the 50 round mag having a
circular internal lip where the standard 5.1 magazine has a square lip.
This may prove to be useful for those that have a habit of handling their
magazines a little more rough causing the magazine lips to break as we all know
corners mean a weak point. By changing the internal corner into a smooth
edge, this will spread any forces exerted on the magazine lip reducing the
chances of any breakage.

Furthermore, due to the elongated magazine lip, the upper part of the
magazine have been made slightly shorter to accommodate the longer magazine lip
with the magazine latch recess placed slightly higher so that the overall
dimensions stay compatible with the HiCapa series. Towards the back of the
magazine lip where it usually hides between the top sides of the magazine shell,
this is not the case with the 50 round mag as it has an enlarged outlet valve
bracket. Upon closer inspection, you will also see that the rubber seal on
the outlet port on the magazine is slightly different to the regular 5.1
magazine as the 50 round magazine has a cornered seal as compared to the square
seal, reducing the friction that comes in during the blowback valve sliding
along the port.

If you look at the base plate between the two magazines, you will also notice
the 50 round magazine has two locking pins towards the bottom of the magazine.
That is used to hold the base plate in where the regular 5.1 magazine's base
plate is held in by a screw hidden underneath the plastic base plate cover which
the 50 round magazine cannot be slid out as you would with the regular
magazines.

We were curious of how many shots it can fire on only one
single charge of gas as well as showing you the main differences between this
extra large mag to the regular 5.1 magazine, so we took it for some gas capacity
tests as well as seeing if there would be any differences on the power output on
these magazines.

Gas capacity vs cooldown test

We understand that the more gas you have reducing pressure,
the lower the temperature will get as it will absorb the energy around it.
Using propane that has an expansion ratio of 1:270 any cooldown effects will be
seen with a bigger effect as compared to using 134a with a much less expansion
ratio hence the power output differences between the two gasses.

Test conditions: firing on quick semi-auto mode using
propane and KSC perfect .20g ammo with an ambient temperature of 27celcius.
Fire using a TM 5.1 HiCapa at quick semi automatic successions until the
magazine is fully expended, reload more ammo immediately and expend the ammo.

On the 50 rounds magazine tested 5 times in total, it was
able to expend on average of 87rounds per charge of gas (25degrees surface temp
before testing and reaching 16celcius after)

where the regular 5.1 mag was able to expend 42rounds
average per charge of gas (25degrees surface temp before, 19degrees after)

Note: Power reduction more noticeable on the standard 5.1
magazine as cooldown effects take its toll where shots become increasingly
weaker along with its recoil, where the 50round mag is less noticeable but power
drops very abruptly in 3-4shots from high kick to hardly any remaining energy to
cycle the slide.

At longer ranges it is easier to achieve a better grouping
due to its additional weight and weight distribution, the 50round magazine adds
more stability by weight and its weight distribution on the lower part of the
pistol on the frame (as compared to a heavier slide where the added weight will
be on the recoil rather than on the body itself)

In a nutshell, if you want to shoot more in one session
without reloading as much but doesn't mind carrying the extra weight on your gun
or your pouches. The 50 rounds magazine has a little more advantage in
terms of firepower without compromising your maneuverability much along with
being able to stabilize your shots for longer ranges due to its increased weight
around the frame making it more manageable to control its recoil due to the
weight balance being more bottom-heavy.